The goal of this proposal is to validate a dietary history questionnaire (DHQ) used in the EARTH cohort study of American Indians and Alaska Natives. The major goal of this parent cohort study is to determine how diet, physical activity, and other lifestyle and cultural factors relate to the development and progression of chronic disease with a long-term goal of understanding relationships with cancer. Therefore, accurate measurement of diet, physical activity and other exposures is essential to the ability to detect meaningful relationships. The DHQ provides a comprehensive assessment of foods and nutrients consumed and the results can be interpreted at the individual level. A self-administered computer-assisted version of the DHQ has been developed for use in the EARTH study Cohort. However, neither the feasibility of using the self- administered computer-assisted DHQ referring to intake over the pas year nor the validity of the DHQ for measuring dietary exposures has been established in American Indians and Alaska Natives. Most information about diet of American Indians and Alaska Natives are based on a single 24-hour recall that does not reflect "usual" individual intake and none about the potential for seasonal variability to influence intake in this population. The aim of this project is to assess the validity of the DHQ with regard to usual intake over the past year. Several components will be evaluated including :1) the relative validity of the self- administered computer-assisted DHQ with regards to nutrient intake (sucrose, energy, fat, fiber, and others), food consumption (fruits, vegetables, and subsistence foods), and dietary patterns (western vs. traditional); 2) reproducibility (reliability) of the DHQ with regards to nutrient intake (sucrose, energy, fat, fiber, and others), food consumption (fruits, vegetables, and subsistence foods), and dietary patterns (western vs. traditional); and 3) differences between computerized-self-administration and self-administered paper and pencil administration of the DHQ on the estimates of nutrient intake (sucrose, energy, fat, fiber, and others), food consumption (fruits, vegetables, and subsistence foods), and dietary patterns (western vs. traditional). [unreadable] [unreadable] [unreadable]